Grate separator



July 18, 1961 c. A. MAYNARD 2,992,734

GRATE SEPARATOR Filed Sept. ll, 1957 F C57.

Char/e5 A. Maf/mrc b @WJHHE 2,992,734 GRATE SEPARATOR Charles A.Maynard, Valparaiso, Ind., assigner to Indiana General Corporation, acorporation of Indiana i Filed sept. 11, 1957, ser. No. 683,286 Claims.('Cl. 209-223) This invention relates generally to grate separators, andmore specifically to an improved grate separator having a means forcleaning thereof incorporated therein.

Although the principles of the present invention may be included invarious separators, a particularly useful application is made inseparators of the grate type which are installed in ducts for removingmagnetic material from a wet or dry mixture passing therethrough.

Such an arrangement may-typically `consist of a hopper below which isdisposed a duct of any cross sectional configuration, and across whichduct are disposed rows of magnets in such an arrangement that anymaterial passing through the hopper also passes through the spacesbetween the magnets of the grate. Thus since the grate is magnetic, andthe spaces between the elements thereof have a magnetic iield, anymagnetic particles are attracted to the grate and retained there.

Devices having such an arrangement have been very eiiective in removingmagnetic material, but are difficult to clean. The magnetic particlestypically adhere very well to the grate, and where the grate comprisespermanent magnets, the problem is particularly acute.

The present invention contemplates the utilization of a thin sleeve overeach of the magnetic grate bars, which sleeve is axially removable fromthe influence of the permanent magnetic eld. In a preferred form of thisinvention, other features are also included which are described morefully herein.

Accordingly, it is an object of the present invention to provide meanswhich permit the easy removal of collected magnetic particles from thegrate.

Another object of the present invention is to provide an improvedmagnetic separator for collecting magnetic particles from a materialflowing therethrough.

Yet another object of the present invention is to provide a means for amagnetic grate separator, which means contacts the substance beingcleaned, and which prevents transfer of magnetic particles to themagnetic grate.

Still another object of the present invention is to provide a means forreleasing the magnetic particles from a magnetic grate separator.

A further object of the present invention is to provide means forreceiving magnetic particles released from a magnetic separator.

A still further object of the present invention is to provide animproved magnetic element for a grate separator.

Many other advantages, features and additional objects of the presentinvention will become manifest to those versed in the art upon makingreference to the detailed description and the accompanying sheet ofdrawing in which a preferred structural embodiment incorporating theprinciples of the present invention is shown by way of illustrativeexample.

On the drawings:

FiGURE l is a fragmentary cross-sectional View of a magnetic grateseparator, partly in elevation, and provided in accordance with theprinciples of the present invention;

FIGURE 2 is an enlarged fragmentary cross-sectional View taken alongline Ii-Il of FIGURE 1;

FIGURE 3 is a fragmentary cross-sectional view taken along line III--IIIof FIGURE 2; and

FIGURE 4 illustrates another manner in which the magnetic elements shownin FIGURE 2 may be assembled.

Eaented iniy 1S, 1951 As shown on the drawings:

The principles of this invention are particularly useful when embodiedin `a magnetic grate separator `assembly such as is illustrated inFIGURE 1, generally indicated by the numeral 10. The separator assembly10 includes generally a housing 11, which supports a magnetic grate 12,surrounded by a means 13 for cleaning the grate 12, a removable tray 14,and a hopper 15 for holding and directing the substance to be cleaned bythe separator. The discharge portion of the housing 11 may communicatewith a duct 16.

It is to be understood that the environment with which the instantseparator assembly has been illustrated herein is exemplary, and -thatthe magnetic separator may be constructed permanently installed or forportable use in a great number of ways.

Referring now to FIGURE 2, the grate assembly 12 is shown in detail. Theassembly 12 may include one or more spaced magnetic bars or barassemblies 17, each having a permanent magnet field extendingtransversely to the direction of iiow of material through adjacentspaces or grate openings 18, whereby magnetic particles in the materialcome under the inuence of such field and are attracted toward 4the bars17.

Referring now to both FIGURES 2 and 3, each of the magnetic bars 17includes a plurality of permanent magnets 19, here illustrated as beingceramic magnets of generally annular configuration. As shown, eachmagnet has a square central aperture and a circular perimeter. It is tobe understood that the outer configuration may be of any desired shape,eg. round or square, and that the central opening may also be of anyshape. In the instant embodiment, a non-circular opening has beenprovided in each magnet whereby when a bolt 2G having a square shank 21is inserted through a plurality of magnets, the poles of each of themagnets 19 are properly 'mdexed with respect to the grate openings 18.The bolt 20 has a threaded end which engages with a non-magnetic end orend member 22. The eld from the various magnets eifectively terminatesat a point deiined by the nonmagnetic member 22. Thus the grate 13includes magnetic bars 17 which mutually have pole faces of oppositepolarity directed toward each other, and each of the mag netic bars 17has radially extending poles mutually aligned in a desired pattern. Thusalso the bolt 20 can comprise any means extending through the variousindividual magnets 19, such means serving to maintain alignment of themagnets, to secure the magnets together as a bar, and to mount the bar17 to one wall 11a of the housing 11.

IIn a second wall 11b of the housing 1=1 opposite to the wall 11a, thereis a means 11c defining an opening 23 for each of the magnetic bars 17.The means 13 for cleaning the grate 12 comprises a tubular member 24extending through the opening 23 and telescopically about each of thebars 17. The tubular member 24 extends outwardly and perferablysubstantially completely encloses the bar 17 The tubular member 24 maycomprise non-magnetic material, but preferably `comprises thin highlypermeable magnetic material through which the field may readily extend.The tubular member 24 thus may be axially or telescopically separatedfrom the magnetic bar 17.

It is apparent that if the mount for the bar 117 were modified, the tube24 could be removed from the other end of the bar 17. Further, it isalso -apparent that the tubular member 24 could ybe made stationary andthat the bar 17 could be relatively withdrawn from the tubular member24. Such construction is less advantageous since access to the exteriorof the tube :for thorough cleaning and for inspection thereof ispreferable. In `any event, the tubular member 24 transmits the magneticfield from the bar 17, and is in contact vw'th the mixture being cleanedand shields the bar `17 from direct contact with magnetic particleswhich are attracted.

While each of the tubular members 24 may be individually withdrawn, theform shown in FIGURE 2 includes a plate 25 which joins the varioustubular members 24 together. A handle 26 is provided for the plate 2S,whereby each oft' the tubular members 24 may be simultaneouslywithdrawn.

At the opposite end ot' each of the tubular members 24. there is aflange 27 which extends radially about each end :to prevent particletransfer about the inner end of the tubular member 24 to the magneticbar 17. Thus the flange 27 comprises 1a radially extending dam which maybe further contoured las shown in FIGURE l to blend with the housing 1&1or hopper 15, thus shielding the bar 17 from the mixture being cleaned,and thereby further precluding the attraction of magnetic particlesdirectly against the bar 17.

When it is desired to clean the separator, that is when it is desired toremove collected magnetic particles from the tubes 24. the flow of themixture through the separator is interrupted, a door 31 is opened. and altray or pan 14 is installed on channels or ways 30 as shown in FIGUREl. The handle 26 is then grasped Iand the shielding assembly 13 is drawnoutwardly. Magnetic particles adiacent to the magnets `are thustranslated laterally and disposed over the non-magnetic member 22 andare thus moved to a position where there is no eld attracting theparticles to :the shield. The particles thereupon fall downwardly intothe tray 14. Tn the event that the particle mechanically adheres to thetube 24, the portion '11e of the housing wall 11b which defines theaperture 23 serves as a scraper for loosening any particle stilladhering to the tube 24. The tube s drawn outwardly until the flange 2-7is positioned in the non-magnetic zone. During this removal, the flangeZ7 also serves to prevent the iumning of magnetic particles from a pointon the outside of the tube 24 to a point remote therefrom of highermagnetic intensity. Thus the flange 27 prevents the umping of lmagneticparticles around the inner end of the tube 24 to any one `of the magnetsdisposed along the length of the bar 17. Usually a single reciprocationof the shield assembly, wherein the flange 27 is moved from a position'adiacent to the secured end of the bar to a position adiacent to thenon-magnetic end of the bar and eturned, is suicient to clean `allmagnetic particles there- While the arrangement of the magnetic poles asshown in FIGURE 2 is advantageous, other arrangements may also be usedto advantage` One alternate arrangement is shown in FIGURE 4 whereinsome of the magnets 19 have been omitted, so that the remaining magnetsare spaced from each other, and wherein the poles of the adiacentmagnets have been oppositely aligned, not only with respect to the`adiacent magnet in the -adiacent bar, but also with respect to theadiacent magnet in the same bar. While the friction between theindividual magnets 19 and the bolt 2d may be suicient to hold thedesired axial spacing, a plurality of non-magnetic sleeves or annularmembers 41 may be used las spacers intermediate adiacent magnets 19 toinsure that the relative axial disposition ot the magnets 19 will remainstationary.

Upon removal of the tray 14, land the mutual or telescopicinterengagement of the magnetic grate and shield assembly, the separator10 is ready for further operation.

Thus a novel structure hasbeen provided which contacts the substance andshields the magnetic elements therefrom, receives `and holds themagnetic particles, prevents particle transfer to the magnetic element,and selectively releases the materials therefrom. Means are alsoincluded for receiving the released particles and creating a magneticfield.

Although various minor modifications might be suggested by those versedin the art, it should be understood that l wish to embody within thescope of the patent warranted hereon, `all such embodiments asreasonably and properly come within the scope of my contribution to theI claim as my invention:

1. A magnetic separator yfor separating magnetic particles from asubstance, comprising in combination: Ia housing; Iat least one tubularmember disposed in said housing for contacting the substance; a magneticbar telescopically received in said member, said bar comprising a seriesof axially-spaced axially-aligned `annular permanent magnets each havinga radius somewhat in excess of its axial length, each having anon-circular `axial opening, and each annular magnet having radiallyextending poles with both north and south polarity at the outerperiphery of each magnet, the poles of each magnet being angularlyaligned with the poles of the adjacent magnets and of opposite polaritythereto, Aa non-magnetic annular member coaxially disposed in each spaceintermediate said magnets, and means having Ia non-circular sectionalconiiguration of a size corresponding to said opening in said magnets,said means extending through said magnets for maintaining said angularalignment and securing said magnets and said non-magnetic memberstogether and securing said bar to said housing.

2. A magnetic bar for a grate separator comprising in combination: aseries of axially-aligned annular permanent magnets each having a radiussomewhat in excess of its axial length, each having a non-circular axialopening, and each annular magnet having radially extending poles withboth north and south polarities at the outer periphery of each magnet,said poles being angularly aligned with the poles of the axiallyadjacent magnets, and means having a non-circular sectional congurationof a size corresponding to said opening in said magnets, said meansextending through said magnets for maintaining said angular alignmentand securing said magnets together.

3. A magnetic bar for a grate separator comprising in combination: aseries of axially-spaced axially-aligned annular permanent magnets eachhaving a radius somewhat in excess of its axial length, each having anoncircular axial opening, and each annular magnet having radiallyextending poles with both north and south polarity at the outerperiphery of each magnet, the poles of each magnet being angularlyaligned with the poles of the adjacent magnets and of opposite polaritythereto a non- -magnetic annular member coaxially disposed in each spaceintermediate said magnets, and means having a non-circular sectionalconguration of a size corresponding to said opening in said magnets,said means extending through said magnets for maintaining said angularalignment and securing said magnets and said non-magnetic memberstogether.

y4. A magnetic separator for separating magnetic particles from asubstance, comprising in combination: a housing having a portion deningan aperture; an imperforate tubular member axially reciprocablyextending through said aperture with a close peripheral lit with saidhousing portion, and disposed to contact the substance; and a magneticbar disposed closely directly within said tubular member and xedlysecured with respect to said housing and telescopically received by oneend of said member to be mechanically shielded thereby from thesubstance, the magnetic eld of said bar substantially terminating at alltimes interiorly of said housing in spaced relation to said aperture;whereby any magnetic particles adhering to said tubular member aremagnetically released when said tubular member is withdrawn from saidhousing and said bar, and simultaneously therewith are scraped from saidtubular member by said aperturedeiining portion.

5. A magnetic separator for separating magnetic particles from a flowingsubstance, comprising in combination: a housing having a portiondefining an aperture; a plurality of magnetically permeable imperforatethin tubular members disposed in spaced parallel relation in saidhousing and axially reciprocably extending through said aperture with aclose peripheral t with said housing portion and disposed for contactingthe substance; and a plurality of magnetic bars each telescopic-allyreceived in closely and directly in one of said tubular members and eachhaving a field strength greater than that needed to magneticallysaturate the same and iixedly secured with respect to said housing; eachof said bars comprising a series of axially-spaced axially-alignedannular ceramic permanent magnets each having a radius somewhat inexcess of its axial length, each having a non-circular axial opening,and each annular magnet having radially extending poles with both north-and south polarity at the outer periphery of each magnet, said magnetshaving axes lying in a common plane normal to the main direction of ovv,said magnets having pole faces so arranged that lines directed from onepole face to the other pole face of the same magnet extend diametricallythereof, and are both perpendicular to the main direction of thesubstance ow, are coplanar and are aligned with a pole face of oppositepolarity in the closest adjacent bar, the poles of each magnet Ialsobeing angularly aligned with the poles of the axially adjacent magnets,and of opposite polarity thereto, a non-magnetic annular membercoaxially disposed in each space intermediate said magnets, and meanshaving a non-circular sectional configuration of a size corresponding tosaid opening in said magnets, said means extending through said magnetsfor maintaining said angular alignment and securing said magnets andsaid non-magnetic members together and securing said bar to saidhousing;

said tubular members being axially reciprocable with respect to thebars, whereby any magnetic particles adhering to said tubular membersare magnetically released when said tubular members are Withdrawn `fromsaid housing and said bar, and simultaneously therewith `are scrapedfrom said tubular members by said aperturedefining portion.

References Cited in the le of this patent UNITED STATES PATENTS2,340,303 Byrd Feb. 1, 1944 2,502,096 Ktilinek Mar. 28, 1950 2,646,883Molins et val. July 28, 1953 2,733,812 Hoi Peb. 7, 1956 2,792,115Medearis May 14, 1957 2,800,230 Thoma July 23, 1957 2,834,359 KearneyM-ay 13, 1958 FOREIGN PATENTS 509,747 Italy Ian. 17, 1955

